(5-1-2015) Google now offers a view of certain buildings' interiors. On a page dedicated to this new feature, Google has provided building owners a way to upload floor plans that can be converted and integrated into Google Maps.
This video was taken using a screen recorder on my Android phone, but the desktop and iOS versions of Google Maps also display this new feature very similarly.
Here is a link to Google's page further explaining how this feature works, and how it is implemented.
https://www.google.com/maps/about/partners/indoormaps/
